1. Field of the Invention
The invention is directed to an improved solenoid valve of the type used, for example, in a hydraulic system such as a vehicle brake system.
2. Description of the Prior Art
FIG. 6 shows a conventional solenoid valve, in particular for a hydraulic unit that is used, for example, in an antilock brake system (ABS), a traction control system (TCS), or an electronic stability program system (ESP). As is clear from FIG. 6, the conventional solenoid valve 600 has a magnet unit 7 with a covering washer 19, and a valve cartridge, which includes a capsule 1, valve insert 5, a tappet 9, a return spring 10, and an armature 8. During manufacture of the solenoid valve 600, the capsule 1 and the valve insert 5 of the valve cartridge are joined to each other by being press-fitted and the valve cartridge is hydraulically sealed in relation to the atmosphere by means of a seal weld 4. In addition, the valve insert 5 absorbs the compressive forces occurring in the hydraulic system and conveys them via a caulking flange 20 to a caulking region 2 on a fluid block 3. In addition, the valve insert 5 conducts a magnetic flux, which is introduced by the magnet unit 7, axially via an air gap 17 in the direction of the armature 8. In addition, the valve insert 5 accommodates the so-called valve body, which constitutes the valve seat 11 into which the tappet 9 is inserted in a sealed fashion in order to perform the sealing function of the solenoid valve 600. As is also clear from FIG. 6, the tappet 9 is guided in the valve insert 5 by a tappet guide 18 and the return spring 10. The lower attachment of the magnet unit 7 is produced by the covering washer 19 being pressed directly against the magnetically conductive valve insert 5 of the valve cartridge. The capsule 1, which is likewise pressed onto the valve insert 5 and welded, has a lower region that is slid in overlapping fashion onto the valve insert 5. In order to be pressed into place, the capsule 1 is slid onto the valve insert 5 by means of a frontal insertion bevel 13. A second insertion bevel is provided for pressing the magnet unit 7 onto the valve insert 5.